Thank you. Your negotiating position is not that strong at the moment, because the employer has not actually done anything wrong legally. I fully empathise that the uncertainty around the potential redundancies can be unsettling but that is not uncommon and the employer is not required to proceed with them within any period of time - they can prolong the process as long as required, they may not even need to make redundancies in the end and all this would have been for nothing.
Your options are to continue working as normal and see where the employer takes this - if they do eventually make you redundant you will keep your redundancy pay and should be paid the bonus in the meantime.
If you wish to leave, you can ask for voluntary redundancy but that can be rejected as there is no obligation on them to consider or grant these.
If you do decide to leave, you will potentially be missing out on redundancy because they can simply let you work your notice period and the termination will be for reasons of resignation, rather than redundancy. If the terms of the bonus are such that you must be still employed at the time it is payable, then try to time any resignation so that you are still employed at that time.
Ensuring you get 3 month unpaid leave is not something you can guarantee - that depends on them. If you can find a reason to get signed off sick long-term (stress can often be used), then that could at least allow you to stay off work for the notice period, whilst remaining employed, however it is up to you as it can go on your personnel record as long-term absence.
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